fix: IS 4.5.0 -> 5.0.0 migration — USD metadata, DomeLight, scene reuse

- Fix USD metersPerUnit/upAxis for IS 5.0.0 (no longer auto-compensated)
- Batch fix all Aligned_obj.usd, table, and art USD files with backups
- Fix DomeLight rotation to Z-axis only (prevent tilted environment map)
- Fix scene reuse across episodes (arena_file caching, task clearing, prim guard)
- Add migration tools: scan_usd_metadata.py, fix_usd_metadata.py
- Add migration guide: migerate/migerate.md
- Add nvidia-curobo to .gitignore
- Fix sort_the_rubbish config: obj_0 -> obj_1 (obj_0 does not exist)

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

workflows/simbox/core/objects/rigid_object.py

@@ -47,6 +47,21 @@ class RigidObject(RigidPrim):
         self.base_prim_path = prim_path
         rigid_prim_path = os.path.join(self.base_prim_path, cfg["prim_path_child"])
         self.mesh_prim_path = str(get_prim_at_path(rigid_prim_path).GetChildren()[0].GetPrimPath())
+        # [LOAD_DBG] Print xformOps right after create_prim, before physics
+        try:
+            from pxr import UsdGeom
+            _xf = UsdGeom.Xformable(get_prim_at_path(rigid_prim_path))
+            for _op in _xf.GetOrderedXformOps():
+                print(f"[LOAD_DBG] {cfg_name} after_create_prim: {_op.GetName()} = {_op.Get()}", flush=True)
+            _l2w = _xf.ComputeLocalToWorldTransform(0)
+            print(f"[LOAD_DBG] {cfg_name} after_create_prim l2w=({_l2w[3][0]:.6f}, {_l2w[3][1]:.6f}, {_l2w[3][2]:.6f})", flush=True)
+            # Also check the USD file's own metersPerUnit
+            _ref_stage = get_prim_at_path(prim_path).GetStage()
+            _mpu = UsdGeom.GetStageMetersPerUnit(_ref_stage)
+            _up = UsdGeom.GetStageUpAxis(_ref_stage)
+            print(f"[LOAD_DBG] {cfg_name} stage metersPerUnit={_mpu} upAxis={_up}", flush=True)
+        except Exception as _e:
+            print(f"[LOAD_DBG] {cfg_name} error: {_e}", flush=True)
         super().__init__(prim_path=rigid_prim_path, name=cfg["name"], *args, **kwargs)
 
     def get_observations(self):